Earlier this month, security researcher Victor Gevers found and disclosed an exposed database live-tracking the locations of about 2.6 million residents of Xinjiang, China, offering a window into what a digital surveillance state looks like in the 21st century.

Xinjiang is China’s largest province, and home to China’s Uighurs, a Turkic minority group. Here, the Chinese government has implemented a testbed police state where an estimated 1 million individuals from these minority groups have been arbitrarily detained. Among the detainees are academics, writers, engineers, and relatives of Uighurs in exile. Many Uighurs abroad worry for their missing family members, who they haven’t heard from for several months and, in some cases, over a year.

Although relatively little news gets out of Xinjiang to the rest of the world, we’ve known for over a year that China has been testing facial-recognition tracking and alert systems across Xinjiang and mandating the collection of biometric data—including DNA samples, voice samples, fingerprints, and iris scans—from all residents between the ages of 12 and 65. Reports from the province in 2016 indicated that Xinjiang residents can be questioned over the use of mobile and Internet tools; just having WhatsApp or Skype installed on your phone is classified as “subversive behavior.” Since 2017, the authorities have instructed all Xinjiang mobile phone users to install a spyware app in order to “prevent [them] from accessing terrorist information.”

The prevailing evidence of mass detention centers and newly-erected surveillance systems shows that China has been pouring billions of dollars into physical and digital means of pervasive surveillance in Xinjiang and other regions. But it’s often unclear to what extent these projects operate as real, functional high-tech surveillance, and how much they are primarily intended as a sort of “security theater”: a public display of oppression and control to intimidate and silence dissent.